Updated August 6, 2019
Author: Mike - FishLore Admin
The Tridacna Maxima Clam also goes by the common name of the giant clam but it's really the small giant clam since the true giant clam is Tridacna gigas. The colors on this clam can be simply outrageous and extremely vibrant. Common mantle colors are blue, green, gold and turquoise with various mantle patterns. They are found all over the Indo-Pacific often in large congregations where there is high light penetration.
The Maxima gets most of their energy needs from the zooxanthellae living within the mantle and need high intensity lighting over the tank. Metal halide and T5's are recommended to keep these clams. Smaller species less than a couple of inches are supposed to be more sensitive to intense lighting and should be adjusted slowly over a period of weeks to higher lighting levels. They will do well when placed on a hard substrate or rock so they can attach.
A often debated topic is whether or not to feed the Maxima clam. Some swear that they need to be fed phytoplankton at least a couple times per week. Others think they do not need to be fed and get most of what they need from their zooxanthellae and filter feeding on ammonia and nitrates from the water column. My take is that it wouldn't hurt to feed them unless you end up polluting your tank. If you see increased growth rates and better coloration when feeding them, why not try?
The Maxima Clam is long lived and needs stable saltwater or reef tank like conditions to thrive. Keep the temperature, salinity, calcium, magnesium and alkalinity levels at natural saltwater levels or slightly higher (see below). Don't keep them with tank mates that will pick at their mantles like hermit crabs and certain fish species that might pick at them such as dwarf saltwater angelfish and large saltwater angelfish.
Maxima Clam Care
Scientific Name : Tridacna maxima
Common Names : Maxima Clam, Giant Clam
Care Level : Moderate to difficult
Size : Up to 12 inches (30 cm)
Life span : Tridacna clams can have very long lifespans
pH : 8.1 - 8.4
Temperature : 75°F - 80°F (25°C - 27°C)
Specific Gravity : 1.023 - 1.025
Carbonate Hardness (dKH) : 8 - 11°
Saltwater Supplements : Needs steady calcium levels (400 - 450 meq/L), Magnesium (Mg) levels need to kept at natural saltwater levels (1250-1380 ppm) and Alkalinity levels (8-10 dKH)
Origin / Habitat : Indo-Pacific, most of the maxima clams these days are aqua-cultured.
Temperament / Behavior : Peaceful and needs to be kept with tank mates that will not bother it.
Aquarium Size : 55 gallon (208 liters) minimum, preferably much bigger water volumes for water parameter stability.
Tank Mates : Stay away from hermit crabs and any other predatory fish species that may nip at the clam mantle.
Diet / Foods : They derive most of their energy requirements from photosynthesis (high output aquarium light such as Metal Halide or T5's) and they are filter feeders and will filter ammonia and nitrates. You can try to feed them phytoplankton or something like Phycopure Reef Blend which has a range of particle sizes. There are several products available for feeding clams. Turn off water flow and using a turkey baster or similar feeding device carefully squeeze the food out a few inches away from the mantle and let the food drift down to them. Sometimes this causes them to clench up. If you have trouble doing it that way, cut the bottom out of a clean 2 liter soda bottle (or milk jug depending on the size of the clam), place the bottle over the clam and while holding the bottle in place with one hand, administer the food to the clam with the other hand. Hold the bottle in place for a minute or two.
Tank Region : Depends on the light intensity in your reef tank. Smaller maximas need to be adjusted slowly to higher output lighting because their mantles are more sensitive than larger clams. I've kept them in the bottom to mid levels of tanks for years under 8x54 watt T5's with excellent results.
Recommended Reading: Giant Clams in the Sea and the AquariumForum Avatar :
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